/* ----------------------------------------------------------------------
 * Project:      CMSIS DSP Library
 * Title:        arm_mat_trans_f32.c
 * Description:  Floating-point matrix transpose
 *
 * $Date:        18. March 2019
 * $Revision:    V1.6.0
 *
 * Target Processor: Cortex-M cores
 * -------------------------------------------------------------------- */
/*
 * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the License); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "arm_math.h"

/**
  @ingroup groupMatrix
 */

/**
  @defgroup MatrixTrans Matrix Transpose

  Tranposes a matrix.

  Transposing an <code>M x N</code> matrix flips it around the center diagonal and results in an <code>N x M</code> matrix.
  \image html MatrixTranspose.gif "Transpose of a 3 x 3 matrix"
 */

/**
  @addtogroup MatrixTrans
  @{
 */

/**
  @brief         Floating-point matrix transpose.
  @param[in]     pSrc      points to input matrix
  @param[out]    pDst      points to output matrix
  @return        execution status
                   - \ref ARM_MATH_SUCCESS       : Operation successful
                   - \ref ARM_MATH_SIZE_MISMATCH : Matrix size check failed
 */
#if defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE)

#include "arm_helium_utils.h"

arm_status arm_mat_trans_f32(
	const arm_matrix_instance_f32 *pSrc,
	arm_matrix_instance_f32 *pDst)
{
	arm_status status;                             /* status of matrix transpose  */

#ifdef ARM_MATH_MATRIX_CHECK

	/* Check for matrix mismatch condition */
	if ((pSrc->numRows != pDst->numCols) || (pSrc->numCols != pDst->numRows)) {
		/* Set status as ARM_MATH_SIZE_MISMATCH */
		status = ARM_MATH_SIZE_MISMATCH;
	} else
#endif /*    #ifdef ARM_MATH_MATRIX_CHECK    */
	{
		if (pDst->numRows == pDst->numCols) {
			if (pDst->numCols == 2) {
				return arm_mat_trans_32bit_2x2_mve((uint32_t *)pSrc->pData, (uint32_t *)pDst->pData);
			}
			if (pDst->numCols == 3) {
				return arm_mat_trans_32bit_3x3_mve((uint32_t *)pSrc->pData, (uint32_t *)pDst->pData);
			}
			if (pDst->numCols == 4) {
				return arm_mat_trans_32bit_4x4_mve((uint32_t *)pSrc->pData, (uint32_t *)pDst->pData);
			}
		}

		arm_mat_trans_32bit_generic_mve(pSrc->numRows, pSrc->numCols, (uint32_t *)pSrc->pData, (uint32_t *)pDst->pData);
		/* Set status as ARM_MATH_SUCCESS */
		status = ARM_MATH_SUCCESS;
	}

	/* Return to application */
	return (status);
}

#else
#if defined(ARM_MATH_NEON)

arm_status arm_mat_trans_f32(
	const arm_matrix_instance_f32 *pSrc,
	arm_matrix_instance_f32 *pDst)
{
	float32_t *pIn = pSrc->pData;                  /* input data matrix pointer */
	float32_t *pOut = pDst->pData;                 /* output data matrix pointer */
	float32_t *px;                                 /* Temporary output data matrix pointer */
	uint16_t nRows = pSrc->numRows;                /* number of rows */
	uint16_t nColumns = pSrc->numCols;             /* number of columns */

	uint16_t blkCnt, rowCnt, i = 0U, row = nRows;          /* loop counters */
	arm_status status;                             /* status of matrix transpose  */

#ifdef ARM_MATH_MATRIX_CHECK

	/* Check for matrix mismatch condition */
	if ((pSrc->numRows != pDst->numCols) || (pSrc->numCols != pDst->numRows)) {
		/* Set status as ARM_MATH_SIZE_MISMATCH */
		status = ARM_MATH_SIZE_MISMATCH;
	} else
#endif /*    #ifdef ARM_MATH_MATRIX_CHECK    */

	{
		/* Matrix transpose by exchanging the rows with columns */
		/* Row loop */
		rowCnt = row >> 2;
		while (rowCnt > 0U) {
			float32x4_t row0V, row1V, row2V, row3V;
			float32x4x2_t ra0, ra1, rb0, rb1;

			blkCnt = nColumns >> 2;

			/* The pointer px is set to starting address of the column being processed */
			px = pOut + i;

			/* Compute 4 outputs at a time.
			 ** a second loop below computes the remaining 1 to 3 samples. */
			while (blkCnt > 0U) {      /* Column loop */
				row0V = vld1q_f32(pIn);
				row1V = vld1q_f32(pIn + 1 * nColumns);
				row2V = vld1q_f32(pIn + 2 * nColumns);
				row3V = vld1q_f32(pIn + 3 * nColumns);
				pIn += 4;

				ra0 = vzipq_f32(row0V, row2V);
				ra1 = vzipq_f32(row1V, row3V);

				rb0 = vzipq_f32(ra0.val[0], ra1.val[0]);
				rb1 = vzipq_f32(ra0.val[1], ra1.val[1]);

				vst1q_f32(px, rb0.val[0]);
				px += nRows;

				vst1q_f32(px, rb0.val[1]);
				px += nRows;

				vst1q_f32(px, rb1.val[0]);
				px += nRows;

				vst1q_f32(px, rb1.val[1]);
				px += nRows;

				/* Decrement the column loop counter */
				blkCnt--;
			}

			/* Perform matrix transpose for last 3 samples here. */
			blkCnt = nColumns % 0x4U;

			while (blkCnt > 0U) {
				/* Read and store the input element in the destination */
				*px++ = *pIn;
				*px++ = *(pIn + 1 * nColumns);
				*px++ = *(pIn + 2 * nColumns);
				*px++ = *(pIn + 3 * nColumns);

				px += (nRows - 4);
				pIn++;

				/* Decrement the column loop counter */
				blkCnt--;
			}

			i += 4;
			pIn += 3 * nColumns;

			/* Decrement the row loop counter */
			rowCnt--;

		}         /* Row loop end  */

		rowCnt = row & 3;
		while (rowCnt > 0U) {
			blkCnt = nColumns ;
			/* The pointer px is set to starting address of the column being processed */
			px = pOut + i;

			while (blkCnt > 0U) {
				/* Read and store the input element in the destination */
				*px = *pIn++;

				/* Update the pointer px to point to the next row of the transposed matrix */
				px += nRows;

				/* Decrement the column loop counter */
				blkCnt--;
			}
			i++;
			rowCnt -- ;
		}

		/* Set status as ARM_MATH_SUCCESS */
		status = ARM_MATH_SUCCESS;
	}

	/* Return to application */
	return (status);
}
#else
arm_status arm_mat_trans_f32(
	const arm_matrix_instance_f32 *pSrc,
	arm_matrix_instance_f32 *pDst)
{
	float32_t *pIn = pSrc->pData;                  /* input data matrix pointer */
	float32_t *pOut = pDst->pData;                 /* output data matrix pointer */
	float32_t *px;                                 /* Temporary output data matrix pointer */
	uint16_t nRows = pSrc->numRows;                /* number of rows */
	uint16_t nCols = pSrc->numCols;                /* number of columns */
	uint32_t col, row = nRows, i = 0U;             /* Loop counters */
	arm_status status;                             /* status of matrix transpose */

#ifdef ARM_MATH_MATRIX_CHECK

	/* Check for matrix mismatch condition */
	if ((pSrc->numRows != pDst->numCols) ||
		(pSrc->numCols != pDst->numRows)) {
		/* Set status as ARM_MATH_SIZE_MISMATCH */
		status = ARM_MATH_SIZE_MISMATCH;
	} else

#endif /* #ifdef ARM_MATH_MATRIX_CHECK */

	{
		/* Matrix transpose by exchanging the rows with columns */
		/* row loop */
		do {
			/* Pointer px is set to starting address of column being processed */
			px = pOut + i;

#if defined (ARM_MATH_LOOPUNROLL)

			/* Loop unrolling: Compute 4 outputs at a time */
			col = nCols >> 2U;

			while (col > 0U) {      /* column loop */
				/* Read and store input element in destination */
				*px = *pIn++;
				/* Update pointer px to point to next row of transposed matrix */
				px += nRows;

				*px = *pIn++;
				px += nRows;

				*px = *pIn++;
				px += nRows;

				*px = *pIn++;
				px += nRows;

				/* Decrement column loop counter */
				col--;
			}

			/* Loop unrolling: Compute remaining outputs */
			col = nCols % 0x4U;

#else

			/* Initialize col with number of samples */
			col = nCols;

#endif /* #if defined (ARM_MATH_LOOPUNROLL) */

			while (col > 0U) {
				/* Read and store input element in destination */
				*px = *pIn++;

				/* Update pointer px to point to next row of transposed matrix */
				px += nRows;

				/* Decrement column loop counter */
				col--;
			}

			i++;

			/* Decrement row loop counter */
			row--;

		} while (row > 0U);          /* row loop end */

		/* Set status as ARM_MATH_SUCCESS */
		status = ARM_MATH_SUCCESS;
	}

	/* Return to application */
	return (status);
}
#endif /* #if defined(ARM_MATH_NEON) */
#endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */

/**
 * @} end of MatrixTrans group
 */
